Welcome back!
Thanks for return to The Binding of Isaac: Repentance devblog.
I’m your host. Last week we interviewed some of the newest members of The Binding of Isaac team (and in the future we’ll interview some of the oldies, too). Vinh, Nik and SAG really opened up and gave some awesome insights into what they were doing before Isaac and what they’re working on now. So we made the decision to divide the interview into two parts so you could get to know them better.
This second part of the interview delves further into the development of the game, the background and some of their process in the making-of.
I really hope you like, we’ll continue to talk to more members of the Isaac team here so if you haven’t already added the game to your wishlist, please do so.
For now, let’s continue where we left off
You're working also closely with the original Rebirth development team on Repentance, which has benefitted the development of the latter significantly.
Vinh: It's pretty crazy to walk in the Rebirth team's footsteps and see how they did things. It's one thing to try to make sense out of the garbled output of a disassembler, but to actually see the code the way it was originally written, and to work with the people who originally wrote it, that's something else entirely.
I'd say my coding style has changed a lot from trying to stay consistent with the code base, I've definitely picked up a few handy optimization tricks here and there and my code is a lot more readable now, I can't even read my own code from Antibirth anymore!
How are you able to nail the style and also resolve your design aesthetic and the needs for the Isaac world?
SAG: Edmund offers very thoughtful information on when something doesn't look right. It's also quite easy to follow! Most of the time I run a design to Vinh and get some feedback from him and Ed to see if something fits. I'm happy with my designs as a result because getting feedback from the big man himself makes it easier to understand how an enemy or boss looks, what it uses to attack, and other things like that.
There have been some stylistic changes to certain monsters that I initially was sad to see go, but now these changes have grown on me and I love and appreciate them now. As for design aesthetic sometimes I imagine a separate Isaac world in my head filled with possible monsters. It helps me narrow down a certain design and then I take some of Ed's elements to make it fit. Will you ever see this separate Isaac world in my head? Maybe, if have the motivation to...
When I was designing the bosses early on, my plan was that "This boss belongs in a room this size" and placing that boss in a room smaller than intended doesn't seem to yield the desired result of increasing the challenge.
Nikola: Yeah, that's pretty much it. Some bosses aren't that bad in small rooms, but if you had a boss that spawned a bunch of troll bombs in a tight room all you could do is pray. While that's pretty fitting for the game's themes, I didn't really have fun in those rooms. Besides, in the much later floors, some of the bosses come back as regular enemies, so I think in that case it's fine.
Are there any limitations for your development needs in the engine that you've encountered and how have you remedied this or worked around it?
I'd say the biggest limitations are shaders, basically what handles all the fancy visual effects. We have to work with a very outdated shader language for the sake of staying compatible with even the oldest machines, I see that as a good thing but it also means there are a lot of features we don't have access to.
It's interesting in a way because it forces us to come up with creative ways to make good looking effects with fairly simplistic code. In Antibirth, Downpour used something called "clipping planes" to cut sprites at their base, giving the illusion of Isaac and all the enemies being partially submerged in water. This is something not all graphics cards supported so we had to get rid of it.
We could have come up with a workaround for it but I never liked that effect in the first place, it looked really awkward with bigger enemies or bosses like Monstro. One of the new floors actually has an effect I'm quite proud of, and it doesn't even use shaders at all! I don't want to get into the details too much but it blends a couple of scrolling layers with the overhead shadow that's visible in most floors to achieve a rather nice atmospheric effect. I hope you'll like it when you see it!
A lot of the effects we did in the original Rebirth series were inspired by classic art effects that wouldn't require the most powerful hardware, you've probably noticed that during your time in development.
Vinh: Honestly I don't think hardware has ever been a limiting factor, Isaac is a retro looking game and while it's fun to add fancy effects that would be impossible on older consoles like the new water shaders, I try not to stray too far away from Isaac's low budget flash game roots.
I suppose one thing I'd add to Isaac if I could would be HDR support. That'd allow for small objects that glow in the dark, or the player's eyes adjusting to the light when moving from a bright room to a dark room and vice versa. This is already something I simulate via shaders but it has its limitations, HDR would make all of that a lot more natural.
Actually, some time before Afterbirth+ released I had a dream about it being revealed at PAX, and it featured HDR support along with some footage of the basement showing off some seriously cool lighting effects, with more vibrant lights and darker shadows. This actually inspired the look of one of the new floors some of you might have seen at PAX West last year!
How different does it feel for you making a mod for a game you love than being one of the people on the dev team responsible for making it happen? Do you feel a different sense of responsibility or about the same?
SAG: Back in the Antibirth days we were all just having a fun time spitballing ideas and making something. We all got to know each other and we all had great hopes and ambitions for the future. Everything was great! We all felt like one big happy family. When working on Repentance, the overall vibe felt... different.
We were all the same three dummies we were when working on Antibirth, but there was a strange sense of seriousness in the air. Like holding a huge weight on your shoulders - an important duty you need to fulfill. It's the same feeling as like, a prince or princess being the next to run a kingdom as a king or queen. Your freedoms and funtimes just sort of... fade, once you get to that place. I share this same responsibility with the others and honestly I feel pretty bad for the delays... time has not been very kind to us, but we still keep our chins up and try to make Repentance the best it can.
How do you merge those new design mechanics seamlessly into "classic" Rebirth design? Do you smile when you imagine surprising a veteran Isaac player with something they've never experience before?
Nikola: I think consistency is important (or at least that's what Vinh's been telling me for years), so making these new rooms still feel consistent with the style of rebirth rooms is fairly important. That familiarity in how rooms are structured is important for long time fans, who instinctively know how to handle a situation. Luckily, by the time brand new players unlock the new repentance floors, you should be familiar enough with the game to not be totally lost.
Also, you bet I'm smiling whenever I put in some weird new mechanic in the game players aren't used to. I'm really looking forward to everyone playing the game and encountering these new rooms and enemies and going "What the hell is that?" I know I like to put in some obscure or rare surprises in my own games 'cus it makes people go on wild goose chases and come up with outlandish theories of what other rare events could be in the game. I really enjoy stuff like that.
That's exactly how we felt when designing really clever traps in 1001 Spikes. IF, and a big IF, this wasn't Isaac and consistency with thousands of other rooms weren't a consideration, what kind of experimentation would you want to do with the rooms?
Nikola: I don't think it would be that much different from what I do now. I think the others would agree, there is comfort in using previous references for consistency. Sometimes coming up with things from scratch is hard and it's good to have a base to fall back on. I think a healthy mix of that and experimentation is what makes for good content.
A lot of your designs are much larger than even some of the largest Rebirth bosses, do you enjoy working in larger scale pixel art and what kind of challenge do you find in it?
SAG: Larger scale pixel art is pretty tough but it is absolutely rewarding in the end. Bigger bosses have all these little details like scratches or wrinkles and it takes some time for it to look perfect. Now multiply that like... 10 or 20 or 40 times...
I'd say it's not harder in a drawing sense, the hardest part is that they require much more detail than small or medium bosses. SPOILER ALERT FOR THOSE THAT HAVEN'T PLAYED ANTIBIRTH. I still remember the time I was making sprites for the Witness. This boss is HUGE. The head alone is almost as big as Delirium's and had much more intricate detail. I believe I started on it 2 weeks before Antibirth was released? Every head took roughly 40 minutes to line, color, and shade. I had to do this like... 10 times?
The Witness also had giant arms and another phase with lots of giant parts... Hay nako I lost so much sleep over this LOL. Repentance has so many weird and wacky monster designs. I really like how Ed is approaching with his designs, many of them using challenging and interesting concepts we have never done before, art and animation wise.
Min Min was a design that grew on me, and I've grown to love the idea of a ghostly girl wearing an empty shell like a jack-o-lantern. For a while there's been one monster that I created that I really like. He's got a big head full of teeth and walks on two stubby feet. At first glance he doesn't sound threatening but he holds a really nasty surprise...
The changes you've made from Antibirth, both as a team and as a game, do you feel it's for the better two years later?
SAG: I think the changes we've made are for the better! Some of them came at a really small cost so I'm totally cool with it. I wonder what the other guys think!
Did you review the original flash codebase?
Vinh: I haven't studied the original Flash codebase, though I think I caught a glimpse of it when looking at the code that governs boss pools. I've seen Florian work on Eternal Edition a couple times and he has a rather unusual way of coding things, which I'm pretty sure I could recognize there! Going from Antibirth to Repentance was pretty smooth, in fact some of the features that took me a long time to code in Antibirth were much easier to achieve in Repentance, mainly because when making a mod, it's much easier to add content than to modify or remove it.
If you wanted to slightly modify the behavior of an existing enemy, the best option was usually to rewrite its AI from scratch, replicating its original behavior, and then adding your own changes. This is something that becomes completely trivial when you're able to modify the original code base. Most of the challenge from porting Antibirth content actually came from redesigning it. There are a lot of things in Antibirth I'm not particularly proud of, and it can be hard to take a step back and rebalance them without being influenced by the original design.
We have a lot of different room sizes and shapes now for the game, is there a specific room type you really enjoy designing?
Nikola: Standard size rooms are my go-to, most of my room ideas are usually normal sized rooms. But despite what I said about Bosses earlier, I really enjoy the occasional small rooms too. Those rooms are way more concentrated and focused which I think is sometimes a neat thing to make something interesting out of. Making rooms I see as solving puzzles, so small rooms are a neat challenge to me. I also like "Tall" rooms, at least more than "Wide" rooms. I'm really not sure why, I think it's cus they resemble squares more. One thing I kinda wish I could do is make bigger rooms be 1 tile longer, so that they have a true middle tile. But I can deal with just making some enemy placements a little asymmetrical, it ain't a big deal.
You've been working together now for a few years. How has your team dynamic changed or grown during this time?
Nikola: Working with Vinh and Sag has been fun. Surprisingly, both Vinh and Sag have the exact same work ethic, so they're both doing some real good work.
It might not feel the same as when we were a scrappy team working on a big rebirth mod back in the day, but at least we've improved how we work together sense then. Some things got easier because we have feedback from Edmund, so it's nice that we don't have to guess what fits in the game anymore.
SAG: I keep some sort of internal clock in mind for when Vinh and Leather are awake, and it's pretty easy to follow. For me, the best time to chat is at night - that's when literally like the other half of the world is awake. Usually in the day I just play games and take naps. Though it hasn't been easy recently, with classes and all...
Throughout the years we've had many ups and downs, some happening to all three of us at the same time. It's made me appreciate working in a small team that knows and understands each other. If I made a game sometime in the future, I would not mind bringing Kil and Leather along...
Vinh: We actually started drifting away from each other for a little while once Antibirth came out, our baby was out there and none of us were really sure about what to do next. Repentance is what brought us back together and I'd say we're closer than we've ever been! Nik and I are actually in the same time zone so we basically talk to each other all the time every day, we don't see Sag around as often but whenever she's around it's always a good time.
Sag was the first person to join the Antibirth team and her art has improved a ton since then. Many of the bosses and enemies from Antibirth have been visually revamped thanks to her (not to mention Maggy's glorious hair) and I think I can safely say Isaac has never looked this good. Seeing her make art for new content is always a huge motivator for me since it's a lot easier for me to imagine how something works if I can see what it looks like.
Nik came in as a guest artist/designer and ended up being our dedicated level man and probably lead enemy designer. His design skills have improved tremendously since Antibirth, many of my favorite new enemies and bosses are designed by him and I know I can trust him when it comes to making room layouts for the new levels. We used to butt heads all the time about enemy or item designs and while we still do, I've come to trust his instincts a lot more.
We're all so close to the end, does the end of this development journey feel similar to that of Antibirth? What are you looking most forward to on release of the game?
Vinh: Oh boy! Things are a lot more tense now that there are so many expectations to meet. Releasing Antibirth was easier because it came out of nowhere, nobody was expecting it, while people have been waiting for Repentance for more than two years... it's a lot of pressure! I hope it will live up to the hype and I'm really excited to watch everyone find all the new secrets. Especially that one.
SAG: The end of this journey carries a different vibe... fans that have played Antibirth know a bit of what to expect and there are also fans who have never seen Antibirth at all, so it feels like we've been developing a full game and a half game at the same time, you know? It's kinda weird now that I think about it...
The initial reaction for Antibirth was the most exciting part. From the surface it looks like a simple mod that adds items and enemies and such... until you get knee-deep in it. That's when it hits you. I'm curious on what everyone will think about Repentance. I hope it'll inspire and encourage fans to make fan art. I love and appreciate everything you guys make, thank you!
Vinh: Oh yeah, it's hard not to feel like we're not adding enough, since the part of the community we interact with the most has already experienced all of Antibirth.
Nikola: It feels the same to me because the end of development happened around the same time of year too. I remember when we were approaching the end of antibirth I would be constantly writing down how much stuff we have left to do and how much time we had left 'cus I like organizing stuff like that and knowing how much a project has progressed. But I think doing that only made the others more needlessly stressed.
I guess you could say I'm equally as worried if we're gonna finish this on time as I was back then. I'm really looking forward to watching all the streamers play repentance, those videos are always pretty good in the first couple of weeks of release when everything is new. I also look forward to seeing how people will adapt to the changes when it comes to regular and high level play. And of course, here's hoping that there's tiny little secrets in the game that are discovered months after release.
If you have one thing to say to people reading about the game, what is it?
Vinh: If you can eat pork, look up "saucisson" and try to get your hands on some, it's one of the tastiest things France has to offer!
SAG: If you see something like a character, a monster, or something that looks either more cuter or more anime than usual, it's probably my fault. I hope you'll like it anyway!
Nikola: Brie…
What do you recommend to a budding artist, programmer designer who wants to get into pro development? Knowing know what you know, what would you tell them to prepare or what to study, how to get ready?
Nikola: What you'll hear from me isn't anything you can't otherwise get from just asking Ed. Just make lots of small projects about small things that interest you, that way you make more mistakes, you learn more, and your games become better for it. Don't be afraid to make mistakes, just make them now and get it over with.
Vinh: If you want to get into programming, don't be afraid to copy, a lot. You'll learn a ton from copying or modifying existing code if you put in the effort to understand it, and you'll get results a lot faster than if you tried to make something from scratch. Modding in general is a great way to learn new things because you already have a base that works, so you can easily make changes, see what happens and learn from it.
Also don't underestimate the usefulness of math, some basic vector math, algebra and calculus can get you a long way, there are a lot of problems in game development that can be solved in a very elegant manner if you understand the math behind them.
I like to think programming and math go very well together because the former helps you understand how useful the latter is. If you want to get into game design, just play games, a lot of them. If there's a game you like, try to understand why you like it, and when you design your own game, try to capture that same feeling. If there's something you don't like in a game, try to understand why, and remember it as an example of what not to do.
SAG: SLEEP. I cannot stress this enough. Think of sleep as a core part for doing tasks. I often joke about not getting enough sleep and end up realizing that's true like 70% of the time... Sleep does wonders for the brain and helps you concentrate on the time you spend doing things. Without that sleep you don't have the energy to have a clear and focused mind, and that's no good. Like, at all.
If you have a heavy job that requires a lot of attention, think of sleep as part of your job. Your boss and your brain (mostly your brain) will thank you for it.
Aside from bug fixes and tuning, what do you want to do after Repentance? Does the team have some ideas?
Vinh: If we're talking non-Isaac stuff, I'd love to work with Nik on one of his games, maybe the three of us could get back together and make something cool.
Nikola: After Repentance releases, I'm hoping we can add some new stuff.
SAG: After Repentance I will sleep for 5000 years. ...joking aside, I hope we'll be able to make more post release content for Repentance, but other than that, I'm uncertain about my future. Someday I'd like to make a game to dump all this weird character lore I've been writing in my off-time. But that's for another time...
Vinh: Sleep sounds nice though...
_
OK, now it's your turn, as we talked about we want to give little glimpse into the people who are making their favorite game. Can you each tell us a little bit about yourselves?
What is it that drew each of you towards Isaac?
The team’s art has very quickly been able to integrate into the art style from the original team. 
You've been doing pixel art for a few years now. 
